Results 91 to 100 of about 3,568,332 (307)

On summation of Fourier series in finite form

Discrete and Continuous Models and Applied Computational Science
The problem of summation of Fourier series in finite form is formulated in the weak sense, which allows one to consider this problem uniformly both for classically convergent and for divergent series. For series with polynomial Fourier coefficients \(a_n,
Mikhail D. Malykh, Ksaverii Yu. Malyshev
doaj   +1 more source

Coefficient-of-Determination Fourier Transform [PDF]

Computation, 2018
This algorithm is designed to perform numerical transforms to convert data from the temporal domain into the spectral domain. This algorithm obtains the spectral magnitude and phase by studying the Coefficient of Determination of a series of artificial sinusoidal functions with the temporal data, and normalizing the variance data into a high-resolution
openaire   +3 more sources

Giant Magnetic Coercivity Driven by Spin‐Bag Ferromagnetism in Epitaxial Sr3YCo4O10+δ Films with Engineered 2D Oxygen Vacancy Ordering

Advanced Functional Materials, EarlyView.
A giant magnetic coercivity and a vertical shift of hysteresis loops are demonstrated in Sr3YCo4O10+δ epitaxial films. The hard magnetic behavior originates from ferromagnetic spin bags stabilized within a long‐range ordered oxygen‐vacancy structure.
Yanbin Chen, Roger Guzman, Xiaomin Jia, Jialu Wu, Xing Xu, Li Sun, Jinbo Pan, Shixuan Du, Myung‐Hwan Whangbo, Wu Zhou, Jing Ma, Ce‐wen Nan, Chonglin Chen   +12 more
wiley   +1 more source

Functions of Minimal Norm with the Given Set of Fourier Coefficients

Mathematics, 2019
We prove the existence and uniqueness of the solution of the problem of the minimum norm function ∥ · ∥ ∞ with a given set of initial coefficients of the trigonometric Fourier series c j , j = 0 , 1 , … , 2 n ...
Pyotr Ivanshin
doaj   +1 more source

Optical Signature of Moiré Superlattices Formed by Twisted SrTiO3 Membranes

Advanced Functional Materials, EarlyView.
We discover optical signatures from bonded interfaces in twisted SrTiO3 moiré superlattices, including low‐frequency Raman vibrational modes and strong second‐harmonic generation, consistent with strong interlayer coupling inferred from cross‐sectional electron microscopy and ab initio calculations. ABSTRACT Moiré superlattices formed at the interfaces
T. A. M. Ragib Shahriar, Fumikazu Murakami, Xing He, Konnor Koons, Xinyan Li, Bumseop Kim, Shihan Qin, Varun Harbola, Jochen Mannhart, Yimo Han, Ruijuan Xu, Shengxi Huang, Andrew M. Rappe, Hanyu Zhu   +13 more
wiley   +1 more source

Ionic Precursors Transformed Into Vinyl Acetate Synthesis Catalyst via Reaction‐Driven Restructuring

Advanced Functional Materials, EarlyView.
This work demonstrates that a simple physical mixture of Pd and Au ionic precursors, KOAc promoter, and SiO2 support can transform into a highly active vinyl acetate synthesis catalyst through reaction‐driven restructuring. The results highlight reaction‐induced restructuring as an innovative and sustainable catalyst design strategy.
Byeong Jun Cha, Welman C. Elias, Hunter P. Jacobs, Kimberly N. Heck, Saghar Rezaie, Sadegh Yazdi, Kiheon Hong, Justin J. Dodson, Laiyuan Chen, Sean G. Mueller, Steven R. Alexander, Michael S. Wong   +11 more
wiley   +1 more source

Extraordinary n‐type Tellurium‐Free Thermoelectric Performance of Y‐Doped BiSe via Synergistic Effect of Vacancies and Band Engineering

Advanced Functional Materials, EarlyView.
Yttrium doping in Sb‐alloyed BiSe synergistically induces Bi vacancies and flattens conduction bands, simultaneously slashing lattice thermal conductivity by 50% and boosting the power factor. The optimized n‐type Bi0.64Sb0.3Y0.06Se delivers a peak zT of 0.91 at 393 K (average zT 0.76, 300–523 K) and an 8‐pair module with 4.6% conversion efficiency ...
Wenhao Xie, Fang Lyu, Xiaolong Sun, Chang Li, Xiaolu Zhu, Liangwei Hu, Qianfeng Ding, Wenjie Zhou, Muyang Huang, Yineng Gou, Yi Zhao, Han Tang, Wei Cao, Yue Hou, Yun Zheng, Ady Suwardi, Ziyu Wang   +16 more
wiley   +1 more source

Giant Electrostriction in Halide Perovskites Revisited With Double‐Modulation Interferometry

Advanced Functional Materials, EarlyView.
A giant electrostrictive effect in lead halide perovskites had been reported previously. This work uses sensitive interferometry to measure the electromechanical response of various halide perovskite samples. The results reveal no intrinsic electrostrictive compression. Instead, the materials expand primarily under an applied electric field as a result
Philipp Ramming, Markus Griesbach, Ralf Moos, Lothar Kador, Anna Köhler   +4 more
wiley   +1 more source

The analytic renormalization group

Nuclear Physics B, 2016
Finite temperature Euclidean two-point functions in quantum mechanics or quantum field theory are characterized by a discrete set of Fourier coefficients Gk, k∈Z, associated with the Matsubara frequencies νk=2πk/β.
Frank Ferrari
doaj   +1 more source

Computing coefficients of Fourier series

Informatica, 1997
Some approaches to the numerical evaluation of Fourier coefficients are outlined. Numerical quadrature formulas of Filon type are developed using higher-order polynomial approximations, in particular third- and fifth-order Hermite interpolants. Adaptive methods of implementation are described.
Plukas, Kostas, Plukienė, Danutė
openaire   +2 more sources